Fabric making



Patented Dec. 19, 1939 UNITED STATES PATENT OFFICE No Drawing.

Application November 12, 1931,

Serial No. 574,671

7 Claims.

My invention relates more particularly to im- 1 provements in lace making but various features thereof will be found useful in various other fields.

The main object of the invention is to provide 5 improvements whereby a foundation or ground fabric may be formed for the lace, embroidery or other element which may be easily removed therefrom and with a minimum loss of time and expense. Further and more specific objects, features and advantages will more clearly appear from the detailed description below.

It has been common in the manufacture of lace to provide a ground fabric or foundation such as chemicalized buckram or crinoline or a sized cotton fabric treated with sulphuric acid, and

the lace is then stitched or formed on this ground fabric and after the lace has been so made the ground fabric is removed therefrom by heating the composite fabric whereupon the ground fabric carbonizes and disintegrates so that the remains thereof may be separated from the lace. This method of removal of the foundation fabric is however, attended with certain disadvantages.

There is a serious risk of destroying or injuring the lace by reason of the generation of acid vapors, produced in the heat necessary to carbonize. This is especially the case when chlorides generating hydrochloric acid on heating are used in etching the ground. For this reason a bland reagent in the removal of the solubilized or temporary fibre is most desirable and by this I mean a reagent without harmful action on the permanent fibre.

By the term solubilized I mean to indicate 35 cellulose treated to make it readily soluble in a reagent or reagents which do not readily dissolve cotton or other cellulose textile fibers in their normal state. By dissolve I mean what may be termed true solution, as of salt in water, and not mere disintegration.

For the cheaper grades of goods, paper has been employed as a foundation, the paper being removed by digestion with water which takes a long time. This method is also unsatisfactory be cause of the tensile weakness of paper permitting the needles to cut across it here and there as the lace is being formed thereon and so producing unsatisfactory work. Other chemical foundations have been suggested but have been found to be relatively expensive as compared with that proposed by me.

According to my invention in its preferred form, I provide a ground or foundation fabric of cellulosic fiber such as cotton and treat the same so that it is rendered relatively soluble with respect to ordinary cotton fabric and then after stitching or forming the lace, embroidery or the like on the foundation fabric, which serves as a support for the lace, embroidery or the like, while the same is being formed, I dissolve away the 5 treated foundation fabric by soaking the same in or passing the same through a solution of a solvent of the treated fabric which is not a solvent of the untreated lace, embroidery, or the like, whereby the foundation fabric is easily, 10 quickly and cheaply removed and the lace, embroidery etc. freed therefrom. By this method I am able to use as a foundation fabric, one of cotton or cellulose fiber which is relatively cheap and yet which has ample tensile strength for 15 the work in question. -While thefoundation fabric of cellulosic fiber may be rendered soluble in various ways, I prefer to do this by using cotton cloth and passing the same through a mixture of sulphuric and nitric acids made by 20 taking 1000 parts by volume of concentrated sulphuric acid of commerce and combining it with 600 parts by volume of strong commercial nitric acid so that the actual amount of H2SO4 is about 60% and the actual HNO; is about 20%. These 25 acids are carefully and slowly mixed while cooling or chilling and stirring and after they are thoroughly mixed and the temperature thereof is reduced to about 60 Fahrenheit, the fabric is introduced therein. This nitrates the cotton 30 forming nitro cellulose, but the fabric still retains its fibrous condition and its strength is not materially weakened. Care must be taken that the acids are not too strong so as to materially weaken the tensile strength of the fabric. Therefore, for any particular fabric it is preferable to make preliminary trials with small pieces of the fabric which are dropped in the mixed acids for about ten minutes and then well washed in cold water and then in hot water and the strength thereof then compared with the original fabric. If it is found that the strength of the fabric is materially weakened, more water should be added to the acids. I find that about 18% of water in the mixture will in many cases be sufficient and result in an acid mixture which will change the cotton fabric into a true nitrocellulose fabric. I prefer to use a mixture of acids which is as strong as possible in the beginning so that the bath will run longer without refortifying, but ,the bath should not be so strong as to materially weaken the fiber. After the fabric has remained in the acid solution for about ten minutes or until the desired modification has been obtained, it is withdrawn from the bath and immediately drenched with a large volume of cold water and given a prolonged washing to remove the acid. It may then be passed through a very dilute solution of carbonate of soda containing about of NazCO: and then dried. The fabric thus prepared is inflammable but it can be rendered substantially flame-proof by treatment with zinc chloride; or the fabric after being taken from the acid bath and washed with cold water may be rendered substantially free from residual acid and at the same time rendered substantially flame-proof by passing the same through a 20% solution of zinc chloride containing a little zinc carbonate in suspension. From this bath the fabric may then be removed and dried. To be more certain of the flame proof quality and the removal of the acid from the fabric, it may again be put through the zinc chloride and zinc carbonate bath if desired. A little glycerine, say amounting to about of the zinc chloride bath, may be added to the bath to promote a softer feel of the finished treated fabric and this also seems to promote solubility of the fabric later.

The fabric may then be used as a ground or foundation on which to stitch or form the lace, embroidery, etc. and after the latter is completed, the ground fabric may be readily dissolved by placing the combination or multiple fabric composed of the lace, embroidery, or the like and foundation, in a caustic soda solution and slightly warming it. The ground fabric should dissolve away rapidly leaving the lace, embroidery or the like free therefrom.

Instead of treating the cotton fabric to form nitrate of cellulose, it may be treated with suitable chemicals to form a fabric or fibers of other cellulose derivatives such as acetate of cellulose or hydro-cellulose, and other solvents may be used in place of the caustic alkali. For example, the nitrated fabric may be dissolved and detached from the lace, embroidery, or the like by using acetone as a solvent or by using a mixture of ether and alcohol or other organic solvents in which case the dissolved fabric instead of forming a product which would go to waste, results in a solution suitable for making lacquers, a collodion, an enamel or waterproofing composition. A slight amount of such solution remaining in the fabric and dried therein is often advantageous. If the ground fabric be treated to form acetate of cellulose it may likewise be dissolved in either caustic soda or organic solvents to form useful by-products as above explained.

Other vegetable fabrics such as fabrics of linen, jute, ramie, etc., may likewise be esterified or otherwise rendered relatively soluble and used as the base fabric and even certain grades of paper may be treated with acids or other chemicals to secure a degree ofhydrolyzation or solubility which brings about a very little weakening of the tensile strength thereof and yet good solubility in caustic liquors or other solvents. The

ground fabric may likewise be rendered relatively soluble by a complex chemical action thereon as for example by producing a fabric, the fibers of which are relatively soluble by reason of being partially hydrolized and partially esterified either at one and the same time or serially via: either by a complex and dual action in one bath of chemical or a series of single actions in sequence. Thus an ephemeral fabric may be formed in various ways wh ch is readily and easily soluble as compared with the lace or other element stitched or formed thereon whereby after the latter has been formed the former may be easily and quickly removed therefrom by solution. Certain features of the invention may be used in other fields as for example, a relatively strong and well solubilized fiber of cotton or cellulose may be used for the purpose of introducing into a single fabric, other and weaker fibers or threads which are relatively non-soluble and then after the production of a single or a complex fabric or of a multiple fabric, the relatively soluble threads may be easily dissolved out leaving the desired fabric formed of the other threads. Therefore certain features of the invention may be utilized in the production of a complex or multiple fabric of various kinds and in the removal therefrom of one or more elements which have been rendered relatively soluble.

By a composite fabric I mean a mixed fabric of variable constituents which may be in one plane or in more than one plane, for example; double weave poplin, which is a mixture of linen and silk, cotton shirting with silk stripes, and other fabrics of this kind. By a multiple fabric I mean a multi-ply fabric.

It will be seen further that I have provided a foundation or reinforcing element for fabrics of various kinds which is easily removed from the finished goods when desired by the simple method of solution and without injury to the remaining permanent fabric or elements thereof and at the same time my invention in its preferred form provides in the resulting solution a useful byproduct capable of various uses.

The fabric may be made of materials modifled and solubilized before spinning or weaving or it may consist of a web or felted sheet that is not produced by textile strand-concatenating operations.

The fabric may be as above described constituted in part of solubilized and in part of insoluble fractions and these parts may be distinguished as structural elements, warp or filling. The warp or filling may be made by twisting solubilized with insoluble threads, or of still more primary textile aggregates. The warp or filling may be made by spinning mixtures of solubilized and insoluble fibres together.

The fabric may be constituted of wholly or partially solubilized elements made before incorporation as a fabric or the solubility may be wholly or fractionally induced in the fabric after production, by application of solubilizing agents to parts of its surface or to its entire area, to any degree of penetration. Moreover, as clearly described, the fractionally soluble parts may consist of piles or places in a multiple fabric or of structural elements in a single fabric orv they may be primary or secondary advances on fibrous raw stock, structural elements or products of spinning, twisting, braiding, knitting, weaving, embroidering, lacemaking, felting, pulping,

screening or other processes preparatory to the manufacture of a fabric, web, sheet or series of such, or the products here mentioned may consist of materials not advanced to fabric or broad goods form such as braids, yarns, twines, cords, tapes, ribbons, etc.

By the term fabric I mean such a fabric as is sometimes designated by the term textile fabric, i. e., not a wire fabric but a sheetlike article made up of textile fibers usually, but not necessarily, in the form of strandlike bodies such as yarns or threads interlaced to form a fabric by' I mean as formed by or occurring in nature, and I do not include artificial strands of material such as artificial silk under this term.

The fabric may be as aforesaid advanced in fabric form by chemical alteration to nitrate, acetate or other solubilized form of cellulose or it may be made from these materials however prepared if in the shape of fabric-forming elements such as yarns, threads, etc. Or as aforesaid it may be made partly of solubilized cellulose and partly insoluble elements and the yarns themselves,-units of fabric constructionmay be of mixed solubilized and insoluble elements. While I have described the treatment of a fabric at some length, I wish to cover the use of any solubilized cellulosic element in a textile or other fibrous aggregate in combination with an insoluble element followed by the removal by solution of the solubilized cellulosic element to produce a useful residual aggregate.

Therefore, while I have described my improvements in great detail and with respect to certain forms and modifications thereof, I do not desire to be limited to such details, forms or modifications since many other modifications and changes may be made and the invention embodied in widely different forms without departing from the spirit and scope thereof in its broader aspects. Hence I desire to cover all the forms and features coming within the language or scope of any one or more of the appended claims.

It will be obvious to those skilled in the art that various modifications may be made in my device without departing from the spirit of my invention and therefore I do not limit myself to what is described in the specification but only as indicated in the appended claims.

its to all common subject matter, this application is a continuation of my application Serial No. 18,032, filed May 24, 1925.

Having thus fully described my said invention what I claim as new and desire to secure by Letters Patent is:

1. The method of making a textile element which consists in treating a structural vegetable textile element in natural form to render it soluble without destruction of said form, combining this with one or more relatively insoluble structural textile elements and directly removing the solubilized element by the use of a solvent alone, which solvent removes, the soluble element without affecting the insoluble textile element.

2. The method of making a textile element which consists in combining a relatively soluble cellulosic textile element which has been rendered soluble in its natural form to render it soluble without destruction of said form with a relatively insoluble cellulosic textile element and then removing the soluble element by the use of a solvent therefor alone.

3. The method of textile composition which comprises combining relatively soluble cellulose ester textile elements which have been rendered soluble .in their natural form withoutdestruction of said form with other relatively insoluble textile elements, and removing the ester elements with a solvent alone.

4. A method of making a fabric which comprises the steps of completely nitrating cotton yarns without destruction of the form of their fibers, combining such yarns into a fabric containing normal cotton yarns, and treating the fabric with a solvent that dissolves the solubilized yarns without affecting the cotton yarns.

5. A method of making a multi-ply fabric which comprises combining strands containing soluble undenitrated nitro-cellulose fibers and strands containing fibers not similarly soluble into a fabric and treating the fabric with a solvent alone to dissolve and remove substantially all of the material of the soluble fibers.

6.A method of making a fabric which comprises the steps of completely nitrating fibers of vegetable origin without destruction of their natural form, combining them into a fabric with unnitrated vegetable fibers, and treating the fabric with a solvent that dissolves the nitrated fibers.

7. The method of making a textile element which consists in combining a relatively soluble cellulosic textile element which has been rendered soluble in its natural form to render it soluble without destruction of saidform, with a relatively insoluble cellulosic textile element and then removing the soluble element by the use of an organic solvent.

JOSEPH F. X. HAROLD. 

